2.1. The Progression of Fibrosis
Progressive fibrosis of liver, kidney, lungs, and other viscera often results in organ failure leading to death or the need for transplantation. These diseases affect millions in the United States and worldwide. For example, hepatic fibrosis is the leading non-malignant gastrointestinal cause of death in the United States. Moreover, it has been increasingly recognized that progression of fibrosis is the single most important determinant of morbidity and mortality in patients with chronic liver disease (Poynard, T. P. et al., 1997, Lancet 349:825-832).
Currently there is no alternative to direct biopsy of affected organs to assess the extent of fibrosis. For all tissues this involves either percutaneous or transbronchial biopsy, procedures whose risks include bleeding, perforation or death. Moreover, biopsy is contraindicated in patients with end-stage diseases in whom there are clotting abnormalities.